mineral

Black Tourmaline (Schorl)

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Hardness: 7-7.5 (Mohs scale); Color: Jet black to brownish-black; Luster: Vitreous to sub-metallic; Crystal Structure: Trigonal (hexagonal prisms with longitudinal striations); Cleavage: Indistinct; Specific Gravity: 3.0-3.26.

Hardness: 7-7
Color: Jet black to brownish-black
Luster: Vitreous to sub-metallic

Identified July 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed in igneous and metamorphic rocks, most commonly in granitic pegmatites. It crystallizes from hydrothermal fluids enriched with boron during the final stages of magma cooling.

Uses & applications

Used primarily in jewelry as a gemstone, as specimens for mineral collectors, and in industrial applications for its piezoelectric and pyroelectric properties (generating electricity from pressure or heat).

Geological facts

Schorl is the most common member of the tourmaline group, making up 95% of all tourmaline in nature. It is heavily associated with grounding and protection in metaphysical circles.

Field identification & locations

Identify in the field by its characteristic three-sided (triangular) prism cross-section and deep vertical striations along the length of the crystals. Commonly found in Brazil, Namibia, Pakistan, and the USA.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Gypsum (variety Selenite or Alabaster)

Calcium sulfate dihydrate (CaSO4·2H2O)

Mineral

Nephrite Jade

Nephrite

Mineral/Rock

Granite

Granite (Phaneritic intrusive igneous rock)

igneous